Before 1880
GEOLOGY
In
ancient times, oceans and then deserts covered Western Colorado.
Their retreat left great deposits including sand, which compressed into
sandstone. To the west of Grand Junction, the red sandstone has
weathered into the canyons and elaborate formations of the Colorado
National Monument. East of the Grand Valley is the vast, flat-topped
Grand Mesa. Volcanic flows had covered that area, forming a protective
layer of hard basalt, hundreds of feet deep. The surrounding terrain
eroded away, leaving the Grand Mesa with its 10,000' elevation, forests
and lakes.
(Monument photo by Al Ligrani)
